JPS60202341A - Pressure-reduction-degree checking device of packed body - Google Patents

Abstract

PURPOSE:To expedite checking, by placing a packed body in a chamber, reducing the pressure in the chamber down to a specified pressure, detecting the amount of swelling change of the container of the packed body by a detector, and determining as the defective product when the amount of the swelling change exceeds a spcified value. CONSTITUTION:A pressure-reduction-degree checking device comprises the following parts: a pressure reducer 13, which stops the pressure reduction when a specified pressure is attained; a detector 14, which detects the amount of swelling change of a container of a packed body 1 that is provided in a chamber 11; and a display part 15, which is linked to the operation of a pressure switch 12, displays the amount of the swelling change when the specified pressure is attained, and lights a lamp when the amount of the swelling change exceeds 4mm.. The packed body 1 is placed in a lower container 10 in the chamber. The pressure in the chamber 11 is reduced. The container of the packed body 1 swells largely at an instant the pressure in the chamber 11 becomes lower than the internal pressure reduction degree. The lamp on the display part 15 is lighted. The lamp is read, and the defective product is determined when the amount of the swelling change exceeds the specified value. Thus the checking can be performed quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the performance inspection of a reduced-pressure package containing a filler such as a food product or a heat insulating material.

Conventional structure and its problems In recent years, in order to improve the insulation performance of the insulation box by increasing the wall thickness, it has been proposed to use a package in which a container is sealed with a filling made of powder such as perlite under reduced pressure. There is. The structure of this package will be explained with reference to FIG. 1. In the package 1, a flexible container 2 made of a plastic-metal laminate film or the like is filled with a filling 3 made of pearlite powder. After reducing the internal pressure to ITorr, the container 2 was sealed.

However, since such a package 1 improves its heat insulation performance by reducing the pressure, if the container 2 is poorly sealed, a predetermined degree of pressure reduction will not be maintained and the heat insulation performance will deteriorate. Therefore, the conventional inspection device for the thermal insulation performance of such a package 1 will be explained with reference to FIG.
It consists of a lower heat plate 6 that maintains a constant temperature of °C and a heat flow sensor 7 that measures heat flow. Then, the package 1 is placed between the upper heat plate 6 and the lower heat plate 6, and the heat flow sensor 7 measures the flow of heat when the package 1 reaches equilibrium with respect to heat transfer. Multiply the thickness of body 1, top,
The thermal conductivity of the package 1 was determined by dividing by the temperature difference between the bottom plates 5 and 6.

Next, the operation of the above conventional example will be explained.

Such a thermal conductivity measurement device 4 measures the thermal conductivity of the package 1 and can determine whether the performance is good or bad, but since the heat flow rate changes depending on the temperature gradient of the package 1, measurement is difficult unless the heat transfer reaches an equilibrium state. Can not. In other words, it is essential that the package 1 is maintained at a constant temperature gradient by the heat flow supplied from the upper heating plate 5 to the lower heating plate 6. As a result, one measurement typically requires an inspection time of 1 to 2 hours. It is also possible to calculate the thermal conductivity from the properties of the heat flow in a non-equilibrium state, but since the package 1 is covered by the container 2 with a thermal conductivity of about 0.2 hl/mh°C, this Under this influence, it is difficult to detect the thermal conductivity of 0.005 mh°C of the filling 3 in the package 1. As a result, it is difficult to inspect all mass-produced undercolor bodies 1 in terms of time, and a large number of inspection devices are required, resulting in a huge investment.

Purpose of the Invention The present invention eliminates the drawbacks of the above-mentioned conventional examples, and makes it possible to inspect the performance of packages in a short time, and contributes to ensuring quality by eliminating defective products due to vacuum breaks and insufficient vacuum through 100% inspection. It is something to do.

Structure of the Invention In order to achieve the above-mentioned object, the present invention provides a chamber for accommodating a package in which a flexible container is filled and the inside pressure is reduced, a pressure reducing device for reducing the pressure in the chamber, and a pressure reduction device provided in the chamber. A detection device that uses an optical displacement transducer to detect the amount of change in the bulge of the container of the packaged product is used to detect the amount of change in the packaged product when the package is left in a chamber and the chamber is depressurized at a predetermined pressure using a decompression device. The amount of change in bulge is detected by a detection device using an optical displacement converter, and a package whose amount of change in bulge is greater than a certain level by the detection device is determined to be a defective product by a half-determined means. .

DESCRIPTION OF EMBODIMENTS The structure of an embodiment of the present invention will be described below with reference to FIGS. 3 and 6, but the same reference numerals will be given to the same conventional structures and detailed explanation thereof will be omitted.

In the figure, reference numeral 8 denotes a reduced pressure degree inspection device for the package 1, which is divided into upper and lower containers 4 and 10, and includes a chamber 11 in which the upper container 9 moves up and down to open and close, and a pressure switch disposed within the chamber 11. 12, a pressure reducing device 13 that stops reducing pressure when the pressure reaches a predetermined pressure by the pressure switch 12, a detection device 14 that detects the amount of change in swelling of the container 2 of the package 1 provided in the chamber 11, and the pressure switch 12.
The display section 16 displays the amount of change in swelling when a predetermined pressure is reached, and a lamp lights up when the amount of change in swelling is 4+++++++ or more.

The detection device 14 includes a laser beam generator 16, an irradiation lens 17, a light receiving lens 18, and a displacement calculator 19. 1, and when the thickness of the package 1 changes, the light receiving position of the light receiving lens 18 shifts, which is converted into a displacement change amount by a displacement calculator 19. The detection device 14 is arranged on the outer surface of the upper container 9, and the upper container 9 has a transparent window 17.
are arranged perpendicular to the optical axes of the irradiation lens 13 and the light receiving lens 14. Also, the package 1 is placed in the chamber 1.
When the chamber 11 is placed in the lower container 1o in the chamber 1 and the chamber 11 is sealed, the light receiving position at this position is input to the displacement calculator 19 as the initial position.

Next, the operation of the above embodiment will be explained.

In the figure, when the package 1 is left still in the chamber 11 and the pressure inside the chamber 11 is reduced by the pressure reducing device 13, the pressure inside the chamber 11 becomes lower than the internal pressure because the degree of internal vacuum of the package 1 is maintained. At the moment when this occurs, the container 2 of the package 1 expands greatly into a balloon shape and its thickness changes. This bulge displacement is detected by the detection device 14. That is, as the container 2 expands, the laser beam irradiated from the irradiation lens 17 is reflected onto the container 2 and enters the light receiving lens 18, but the light receiving position in the light receiving lens 18 shifts, and the displacement calculator 19 responds to this shift. It is converted again as a movement amount. Then, when the pressure within the chamber 11 reaches a predetermined degree of pressure reduction, the pressure switch 12 is activated to stop the pressure reduction device 13.

At this time, the amount of change in bulge measured by the detection device 14 is simultaneously input to the display section 16. Therefore, in the case of a bulge change of 4 or more, the display section 150 lamp lights up. Therefore, if the internal pressure of the package 1 is higher than the predetermined pressure, the container 2 will expand beyond a certain size and the lamp on the display section 16 will light up, and on the other hand, if the pressure is low, the container 2 will expand to the display section 16. The lamp does not light up. Therefore, by reading the lamp on the display unit 16, it is possible to determine whether the internal pressure of the package 1 is higher or lower than a predetermined pressure.
It is possible to judge pass/fail for defective products due to vacuum breaks or insufficient decompression, and it is also possible to judge whether the insulation performance is good or bad.

In other words, there is a close relationship between the degree of internal vacuum and thermal conductivity of the package 1, and if the type of filler 3 such as foamed perlite is constant, measuring whether the degree of internal vacuum is at a predetermined pressure will determine the predetermined heat. It is possible to judge whether conductivity is obtained or not.

In addition, even if the package 1 has a small scratch such as a needle hole, and the degree of internal decompression shows atmospheric pressure, and the air inside and outside the package 1 circulates through the scratch, the chamber Even if the pressure in the packing 9 is reduced, the air in the filling 3 can easily be removed from the package 1.
Since the pressure is higher than the degree of vacuum inside the chamber 9 and the pressure is high compared to the degree of vacuum inside the chamber 9, expansion changes occur in the same way as a vacuum break or insufficient vacuum.

As an example, 0.00701 g'm, h'C (internal pressure 1.0 Torr), and 0. oo8olarL/mh℃
(internal pressure 2.0 Torr) The thickness expansion displacement under reduced pressure of the package 1 is 5% from the internal production capacity.
It suddenly expands when the chamber is decompressed at a relatively low pressure. (As shown in FIG. 4.) The heat insulation performance of the package 1 can be easily estimated from the correlation between the degree of vacuum in the chamber 11 and the thermal conductivity of the package 1 (shown in FIG. 5) at this time. Therefore, if a package 1 with a thermal conductivity higher than a predetermined value is determined to be a defective product, the pressure inside the chamber 11 is reduced to a predetermined pressure corresponding to this thermal conductivity, and the detection device 14 detects that the package 1 has a bulge of 4 or more. As a result, the display section 15 lights up the lamp, and it can be determined that the product is defective. Therefore, it is possible to easily inspect all defective products such as vacuum breaks or insufficient vacuum, which contributes to ensuring process quality.

In addition, since the amount of displacement change is detected by the optical detection device 14, there is no mechanical influence such as load on the expansion of the container 2 of the package 1, so the amount of displacement change does not vary and the accuracy and reproducibility are improved. There is no problem with that. Furthermore, even if the thickness of the package 1 is not constant, the time point when the chamber 11 is sealed is input as the initial position, so packages 1 having different thicknesses can be used continuously without any problem.

Although the embodiment has been described using a heat insulator pack as an example, the present invention can also be used to inspect the reduced pressure of retort food, etc., which has been sealed with food or the like inside and has been reduced in pressure.

Effects of the Invention The present invention has the above-mentioned configuration, and the package is placed in a chamber, the chamber is depressurized to a predetermined pressure, and the amount of change in the bulge of the container of the package is detected by a detection device, and the amount of change in bulge is detected. When the size is above a certain level, the product is determined to be defective by the quality determining means, so that the degree of internal vacuum of the package can be easily inspected, and a vacuum break or insufficient vacuum can be determined. Also,
Since the detection device is an optical type, there is no mechanical influence such as load on changes in the swelling of the packaging container, and it has excellent accuracy and reproducibility. Furthermore, even if the thickness of the package is not constant, the time point when the chamber is sealed is input as the initial position, so packages with different thicknesses can be used continuously without any problem.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the package, Fig. 2 is a front view of a conventional inspection device, Fig. 3 is a sectional view of a horizontal banner device in an embodiment of the present invention, and Fig. 4 is a chamber of the package under reduced pressure. FIG. 5 shows a relationship between the thermal conductivity of the package and the degree of vacuum in the chamber. 1... Packaging body, 2... Container, 3...
...Filling, 11...Chamber, 13...
... Pressure reduction device, 14 ... Inspection button device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
1B! 1 Figure 2 'l Figure 3

Claims (1)

[Claims] A chamber for accommodating a package whose interior is depressurized by filling a flexible container, a decompression device for reducing the pressure in this chamber to a predetermined pressure, and a bulging of the package provided in the chamber. A depressurization degree inspection device for a package, comprising a detection device for optically converting the amount of change into displacement, and a quality determination means for determining the product as defective when the amount of change in bulge is determined by the detection device to be a certain value or more.